Objective. To study the correlation of cytomorphological features in fine needle aspiration smears from patients suspected of having tuberculous lymphadenitis with Ziehl-Neelsen staining (ZN), auramine-rhodamine staining (ARS), and autofluorescence (AF). Methods. A total of 145 lymph nodes were aspirated, 3 air-dried smears were stained with Giemsa, Ziehl-Neelsen, and auramine-rhodamine stains, and 1 smear was wet fixed for Papanicolaou staining. Needle washes were incubated in Lowenstein-Jensen medium for culture. Papanicolaou and auramine-rhodamine stained smears were examined under fluorescent microscope using a blue excitation filter (450–480？nm). Results. Ninety aspirates were reported on cytomorphology as suggestive of tuberculous lymphadenitis. Smear positivity for Mycobacteria by Ziehl-Neelsen method was 26.67% (24/90), while positivity increased to 34.44% (31/90) by auramine-rhodamine and 42.22% (38/90) on autofluorescence. Culture was positive in 27.78% (25/90) aspirates. Using culture as the reference method, the statistical values of ZN, ARS, and AF were as follows: sensitivity 80.0%, 88.0%, 96.0%; specificity 93.85%, 86.15%, 78.46%; positive predictive values 83.33%, 70.97%, 63.16%; and negative predictive values 92.42%, 94.92%, 98.08%, respectively. Conclusion. There is a definite advantage of autofluorescence over Ziehl-Neelsen and auramine-rhodamine which is to detect Mycobacteria, being more sensitive as well as an inexpensive technique. Autofluorescence can be a useful addition to routine cytology for early diagnosis and effective treatment. 1. Introduction Tuberculosis (TB) is a major health problem in developing countries. Lymphadenopathy is the most common presentation of extrapulmonary tuberculosis [1, 2]. The precise cause of these enlarged lymph nodes is often difficult to establish by history, physical examination, and radiographic studies alone. Fine needle aspiration cytology (FNAC) has assumed an important role in the evaluation of peripheral adenopathy as a possible noninvasive alternative to excisional biopsy [3]. The cytological criteria for the diagnosis of possible tubercular lymphadenitis have been clearly defined as epithelioid cell granulomas with or without multinucleated giant cells and caseation necrosis [4]. Culture is essential for a definitive diagnosis; however, it takes weeks for identification, and its sensitivity is also relatively low in paucibacillary conditions [5, 6]. Conventional Ziehl-Neelsen (ZN) method for acid-fast bacilli (AFB) plays a key role in the diagnosis and the monitoring of treatment in
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